Troubleshooting for roller chain and applications

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PROBLEM	POSSIBLE CASES	ANSWER
Chain climbing or jumping off the sprocket teeth	Chain or sprockets worn	Replace the chain and sprockets if necessary
	Chain excessively slack	Adjust the center distance or introduce a jockey sprocket to take up the slack. If allowable, shorten the chain
	Insufficient chain wrap	For large raito drives the driver sprocket may not have enough teeth to absorb the working tension. If the drive cannot be altered, introduce a jockey sprocket to increase the chain wrap
	Foreign material build up in the sprockets tooth gaps	Clean the sprocket teeth of all material so that the chain engages correctly
Chain Drive Running Hot	Lubrication method or type of lubrication is unsuitable for the operating speed and power being transmitted	Check the catalogue selection tables for the correct lubrication method
	Insufficient lubrication	Increase the frequency of lubrication in line with good maintenance practice
	Chain continually hitting an obstruction	Remove the obstruction
	Incorrect chain size selected for the speed and transmitted power	Check the chain selection as a smaller pitch or multistrand chain of equivalent capacity may be required
Chain elongation (A gradual increase over its life is normal)	Lubrication failure	Replace chain and sprockets
	An overload	Check lubrication, drive configuration and loadings
	Displacement of the bearings	Monitor drive elongation over a period of 2-3 months by checking the degree of sag
	Failure of the tensioning device	Contact our technical staff for advice if problem persists
Chain stiffens, starts to whip	Worn chain or sprockets	Replace chain and sprockets
	Excessively slack chain	Adjust centres if possible or introduce a take-up system such as a jockey sprocket. it is also possible to shorten the chain by one or more pitches
	Heavy & impulsive load	Reduce the loading
	Centre distance too long	Add a jockey sprocket on long centre distances
	One or more stiff joints	Remove or repair stiff joints
Excessive noise	Misalignment of sprockets	Misalignment introduces abnormal loading and wear. Recheck alignment to maintain normal drive conditions
	Inadequate lubrication	Improve the lubrication method to ensure the proper amount of lubrication is available in the bearing areas
	Worn or incorrectly fitted bearings	Replace or correct the bearings as these will malign the entire drive
	Chain excessively slack or tight	Adjust the centre distance if possible or introduce a jockey sprocket
	Worn chain or sprockets	Replace the chain and where necessary the sprockets. Consider hardened teeth
	Tight joints	Replace or repair joints
	Heavy impulsive loads	Reduce the load or introduce a jockey sprocket
	Chain pitch size too large	Check the chain selection or contact our technical staff
	Obstruction in the chains path	Remove the obstruction
Heavy wear on sprocket Teeth working faces. (A bright polished appearance Is normal)	Poor lubrication	Improve the method of lubrication, (see lubrication section)
	Presence of abrasive	Check for presence of foreign materials and eliminate the source. Replace sprockets and chain if necessary
Pin fails	System loading is greater than the capacity of the chain	Check the kilowatt rating table to determine if the chain capacity has been exceeded. Larger pitch chain or a multistrand chain may be required if the load conditions cannot be corrected
Roller or bush fails	Chain capacity has been exceeded at high speed causing impact on the sprocket teeth	Check the drive selection. A smaller pitch chain, a multistrand chain or sprockets with more teeth may be required
Roller or bush fails	Tooth marks on the outside of the roller diameter can initiate failure	If the rollers are marked by the sprocket teeth, adjust the centre distance
Rust present on chain	Inadequate lubrication. This will also affect the joints which will be discoloured, (light to dark brown) and could be rough, grooved or galled	Remove several joints and check that the components are not severely damaged. Replace chain and sprockets as necessary Improve lubrication method
Side plate fails	Fatigue failure is caused by repetitively loading the chain above its limit	Check the drive selection, a larger pitch chain or a multistrand chain may be required
Side plate fails	Impulsive drive conditions can also cause fatigue failure	If not the above, check for excessive slack. This may indicate worn chain and sprockets. Replace where required
Side plates are worn	Wear on the inside of the plate is caused by sprocket misalignment	Check and adjust sprocket and shaft alignment
Side plates are worn	Wear on the top of the side plate is caused by the chain rubbing against the chaincase or some obstruction	Remove source of rubbing by removing the obstruction or adding a jockey sprocket to control the slack in the chain
Wear on the sides of the sprocket teeth	Drive misalignment	Check and correct sprocket and shaft alignment